Getting some push-back from relatives regarding my diet which now not only includes Very Low Carbohydrate (VLC) regime but also a Intermittent Fasting (IF) component. I eat one VLC meal a day for dinner. Some of my relatives seem to think that this sort of regime is “not good for me”. Specifically they have a problem with the fasting part. Let’s see what the experts say.

First let me lead off with the first article below regarding Calorie Restriction which is the only proven way to radically extend life on test animals. The Wiki link explains that they are seeing increases of 30 to40% in the life spans of rats and mice. In primates the results are not yet final as they tend to live a lot longer. But so far in the 20th year of the study 80% of the calorie restricted monkey’s are still alive compared to 50% of the controls. Additionally the dieting monkey’s show significantly less diabetes, cancer, and heart and brain disease.

GAINESVILLE, Fla. — Reduce, recycle and rebuild is as important to the most basic component of the human body, the cell, as it is to the environment. And a University of Florida study shows just how much the body benefits when it “goes green,” at least if you’re a rat: Cutting calories helps rodents live longer by boosting cells’ ability to recycle damaged parts so they can maintain efficient energy production. via University of Florida News – UF scientists reveal how dietary restriction cleans cells.

So then after that article let’s discuss a way of perhaps getting the same results without having to starve all the time. First off a study showing that the protective effects of Calorie Restriction (CR) are also seen in patients who fast but while calorie restriction can take weeks to months to be effective, fasting gives results within days. From the study:

Preliminary reports indicate that fasting for up to 5 days followed by a normal diet, may also protect patients against chemotherapy without causing chronic weight loss. By contrast, the long-term 20 to 40% restriction in calorie intake (dietary restriction, DR), whose effects on cancer progression have been studied extensively for decades, requires weeks-months to be effective, causes much more modest changes in glucose and/or IGF-I levels, and promotes chronic weight loss in both rodents and humans.

Chronic calorie restriction has been known for decades to prevent or retard cancer growth, but its weight-loss effect and the potential problems associated with combining it with chemotherapy have prevented its clinical application. Based on the discovery in model organisms that short term starvation (STS or fasting) causes a rapid switch of cells to a protected mode, we described a fasting-based intervention that causes remarkable changes in the levels of glucose, IGF-I and many other proteins and molecules and is capable of protecting mammalian cells and mice from various toxins, including chemotherapy. Because oncogenes prevent the cellular switch to this stress resistance mode, starvation for 48 hours or longer protects normal yeast and mammalian cells and mice but not cancer cells from chemotherapy, an effect we termed Differential Stress Resistance (DSR). In a recent article, 10 patients who fasted in combination with chemotherapy, reported that fasting was not only feasible and safe but caused a reduction in a wide range of side effects accompanied by an apparently normal and possibly augmented chemotherapy efficacy. Together with the remarkable results observed in animals, these data provide preliminary evidence in support of the human application of this fundamental biogerontology finding, particularly for terminal patients receiving chemotherapy. Here we briefly discuss the basic, pre-clinical, and clinical studies on fasting and cancer therapy.

So does IF mimic the effects of CR? Here is an article in Nature that says it does mimic CR without an overall calorie decrease.

Dietary restriction is the most effective and reproducible intervention to extend lifespan in divergent species1. In mammals, two regimens of dietary restriction, intermittent fasting (IF) and chronic caloric restriction, have proven to extend lifespan and reduce the incidence of age-related disorders2. An important characteristic of IF is that it can increase lifespan even when there is little or no overall decrease in calorie intake2. The molecular mechanisms underlying IF-induced longevity, however, remain largely unknown. Here we establish an IF regimen that effectively extends the lifespan of Caenorhabditis elegans, and show that the low molecular weight GTPase RHEB-1 has a dual role in lifespan regulation; RHEB-1 is required for the IF-induced longevity, whereas inhibition of RHEB-1 mimics the caloric-restriction effects. RHEB-1 exerts its effects in part by the insulin/insulin growth factor (IGF)-like signalling effector DAF-16 in IF. Our analyses demonstrate that most fasting-induced upregulated genes require RHEB-1 function for their induction, and that RHEB-1 and TOR signalling are required for the fasting-induced downregulation of an insulin-like peptide, INS-7. These findings identify the essential role of signalling by RHEB-1 in IF-induced longevity and gene expression changes, and suggest a molecular link between the IF-induced longevity and the insulin/IGF-like signalling pathway.

Source

Abstract

Disruption of autophagy–a key homeostatic process in which cytosolic components are degraded and recycled through lysosomes–can cause neurodegeneration in tissue culture and in vivo. Upregulation of this pathway may be neuroprotective, and much effort is being invested in developing drugs that cross the blood brain barrier and increase neuronal autophagy. One well-recognized way of inducing autophagy is by food restriction, which upregulates autophagy in many organs including the liver; but current dogma holds that the brain escapes this effect, perhaps because it is a metabolically privileged site. Here, we have re-evaluated this tenet using a novel approach that allows us to detect, enumerate and characterize autophagosomes in vivo. We first validate the approach by showing that it allows the identification and characterization of autophagosomes in the livers of food-restricted mice. We use the method to identify constitutive autophagosomes in cortical neurons and Purkinje cells, and we show that short-term fasting leads to a dramatic upregulation in neuronal autophagy. The increased neuronal autophagy is revealed by changes in autophagosome abundance and characteristics, and by diminished neuronal mTOR activity in vivo, demonstrated by a reduction in levels of phosphorylated S6 ribosomal protein in Purkinje cells. The increased abundance of autophagosomes in Purkinje cells was confirmed using transmission electron microscopy. Our data lead us to speculate that sporadic fasting might represent a simple, safe and inexpensive means to promote this potentially therapeutic neuronal response.

Finally let me close with the always interesting Mark Sisson from the Mark’s Daily Apple. Here is a snippet from what I believe is the first article he ran on IF.

The results were surprising and impressive.

Numerous animal and human studies done over the past 15 years suggest that periodic fasting can have dramatic results not only in areas of weight (fat) loss, but in overall health and longevity as well. A recent article in the American Journal of Clinical Nutrition gives a great overview of these benefits which include decreases in blood pressure, reduction in oxidative damage to lipids, protein and DNA, improvement in insulin sensitivity and glucose uptake, as well as decreases in fat mass.

How can you argue with results like these? And it all makes sense from an evolutionary perspective, because our predecessors almost certainly went through regular cycles where food was either abundant or very scarce. The body may have established protective mechanisms to adapt to these conditions by sensitizing insulin receptors when it was critical that every bit of food be efficiently used or stored (as in famine), or by desensitizing them when there was a surplus, so the body wouldn’t be overly-burdened by grossly excessive calorie intake.

Beyond insulin sensitivity, it appears that caloric restriction and intermittent fasting may “turn on” certain genes that repair specific tissues that would not otherwise be repaired in times of surplus. One could surmise that this adaptation serves to allow certain cells to live longer (as repaired cells) during famine since it’s energetically less expensive to repair a cell than to divide and create a new one. That might help explain some of the extended longevity seen in animal studies using caloric restriction and/or intermittent fasting (read about here, here, andhere). Intermittent fasting has also been shown to reduce spontaneous cancers in animal studies, which could be due to a decrease in oxidative damage or an increase in immune response.

He goes on to say in this latest article:

Why Fast? Part Two – Cancer“Everyone has a physician inside him or her; we just have to help it in its work. The natural healing force within each one of us is the greatest force in getting well. Our food should be our medicine. Our medicine should be our food. But to eat when you are sick is to feed your sickness.” – Hippocrates

For thousands upon thousands of years (during most of which overweight, let alone obese, people were fairly rare), therapeutic fasting was a common protocol for the healing of many a malady. From famous sages like Plato, Aristotle, and the aforementioned Hippocrates and Plutarch to cancer patients unable to eat during chemotherapy to pet dogs and cats who suddenly lose once-voracious appetites upon falling ill, it seems like the natural response to – and perhaps therapy for – major illness is to stop eating for a while.

For thousands upon thousands of years (during most of which overweight, let alone obese, people were fairly rare), therapeutic fasting was a common protocol for the healing of many a malady. From famous sages like Plato, Aristotle, and the aforementioned Hippocrates and Plutarch to cancer patients unable to eat during chemotherapy to pet dogs and cats who suddenly lose once-voracious appetites upon falling ill, it seems like the natural response to – and perhaps therapy for – major illness is to stop eating for a while.

Now, “natural” is not always good. “Is” does not necessarily imply “ought.” But I think the persistence of this phenomenon throughout nature demands that we look a little more closely into whether or not there’s something to it. From babies putting items they found on the ground into their mouths to introduce novel bacteria to their bodies, to weight lifters craving meat after a hard workout to introduce protein to their hungry muscles, to pregnant women experiencing strong food aversions to minimize the chance of introducing a toxin or poison to the growing fetus, I’m generally of the opinion that there’s usually a physiological explanation for most of our odd cravings and behaviors. I see no reason why a sudden lack of appetite wouldn’t have a similar explanation – especially one that transcends species. What if skipping meals for a day or two kickstarted internal healing in some way? Is that really so outlandish? You already know where I stand on the importance of lessons learned from watching our animal companions, and I think this time is no different.

Luckily for us, we aren’t just flailing around and making guesses. Modern science has deigned research into the phenomenon, particularly regarding cancer, worth pursuing.According to Valter Longo, a cancer researcher from USC, “normal cells” go into survival mode during starvation. They display “extreme resistance to stresses” until the “lean period” ends, much like an animal in hibernation mode. Cancer cells, on the other hand, are always “on.” Their “goal” is to grow and reproduce and consume resources. For cancer cells, there is no novel survival mode to switch on. If this is the case, fasting should both improve our resistance to cancer and our body’s ability to survive it (and the treatments used against it, like chemotherapy).

Taking all of this into account if you are past 40 you should be looking into this as a means of making your later years more enjoyable.

Naomi I began IF as an attempt to break through a plateau in weight that I had run into. Even at less than 20 grams of carbs a day my weight was stuck at 205 for months. By following IF my weight dropped to 195.

If you think it’s cool that IF gets you all of the benefits of CR without actually restricting calories, then you’ll be interested to know that simply fasting from carbs and excess protein will get you all of the benefits of IF without totally abstaining from food. :)